It has been estimated that worldwide there are about 260–270 recentspecies of naticid snails.[1] This group is assumed to have originated in the late Triassic or in the early Jurassic.[1] Members of this family can be recognized by the shape of their shells, distinct appearance or by their predatory behavior.[1]

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Naticids are widely distributed and occur worldwide. The greatest diversity of both species and genera is found in tropical regions. Even so, naticid snails are also plentiful in temperate, Arctic and Antarctic waters.[1]

Moon snails live on sandy substrates, at a great variety of depths depending on the species (from the intertidal zone to thousands of meters in depth).[1] They are often seen ploughing along in the sand searching for prey.

A fossil shell of Naticarius millepunctatus from the Nicosia Formation, Pliocene, Cyprus

Naticids are predatory, feeding mostly on bivalves. They will also attack almost any other shelled mollusk they encounter in the sand, such as scaphopods and other gastropods, including other moon snails.[1] Additionally, Conuber sordidum was shown to prey on the soldier crab Mictyris longicarpus (Crustacea) by drilling predation.[3][4] To catch soldier crabs, C. sordidum uses the same behaviour as when hunting shelled molluscan prey.[4]

The moon snail envelops the prey and then bores a hole through the shell using its radula and an acid secretion. Once the shell is bored open, the proboscis is used to consume the flesh of the prey. The hole in the shell, which has a "countersunk" appearance with chamfered edges, and which varies in size according to the species, is a characteristic diagnostic sign of moon snail predation.

In the breeding season, the female moon snail lays a rather stiff egg mass which includes sand and mucus. These objects wash up on sandy beaches fairly often, and are known by the common name "sand collars" because of their resemblance to an old-fashioned removable shirt collar or false-collar.

^Bandel K. 1999. On the origin of the carnivorous gastropod group Naticoidea (Mollusca) in the Cretaceous with description of some convergent but unrelated groups. Greifswalder Geowissenschaftliche Beiträge, 6, 134-175.